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Undoubtedly, no biomarker has had more profound impact on our approach to cancer detection, staging, and monitoring after treatment than the prostate-specific antigen (PSA)7 test. PSA is a serine protease produced by the prostate epithelium, secreted into seminal fluid, and measurable in peripheral blood by immunoassay laboratory techniques detecting both free unbound forms and that bound to the protease inhibitor α1-antichymotrypsin. The introduction of the PSA test as a diagnostic means to monitor and detect prostate cancer during the 1980s was based on discoveries in the laboratories of Kuriyama, Wang, and Papsidero, together with observations in clinical cohorts never exposed to screening by Stamey, Catalona, and others, noting that men with prostate cancer (or benign prostatic hyperplasia) had higher PSA concentrations compared with healthy controls (1). The PSA test was far more sensitive than assays of prostatic acid phosphatase and digital rectal examination. These findings set off a rapid widespread introduction of the PSA test in clinical practice, mainly in the US, which contributed to a dramatic surge in prostate cancer incidence in the US during the late 1980s through the mid-1990s. There is clear evidence from large population-based randomized trials—the European Randomized Study of Screening for Prostate Cancer (ERSPC) and the Goteborg randomized screening trial—that early detection (and concomitant management) by PSA screening reduces a man's risk of dying from prostate cancer. Indeed, extensive use of PSA testing has importantly contributed to a 40% to 50% decline in prostate cancer mortality in the US between 1993 and 2015. However, the widespread use of PSA testing of asymptomatic men, combined with liberal criteria to perform a prostate biopsy, has led to important harms associated with the overdiagnosis of tumors that would never have caused symptoms or harm during a man's lifetime, as well as consequential risk of unnecessary treatment. …

Objective. To characterize the disease progression and median survival of patients with prostate cancer (PCa) according to the prostatic-specific acid phosphatase (PAP) analysis in a population-based study from the Surveillance, Epidemiology, and End Results (SEER) database.Materials and Methods. Prostate cancer patients with completed PAP results were identified using the SEER database of the National Cancer Institute. The Mann-Whitney Sum test was utilized to compare the statistical significance for measurement data and ranked data. Data were stratified by ages, races, TNM Classification of Malignant Tumors (TNM), pathological grades, number of tumors, PAP, and survival duration. Multivariable logistic analysis was performed to identify predictors of the presence of invasion and metastases. Cox regression was analyzed for the factors associated with all-cause mortality and prostate cancer-specific mortality. Moreover, survival curve was used to detect the survival months. The unknown data were excluded from these tests.Results. In total, there are 5184 PAP+ patients and 3161 PAP- patients involved. The Mann-Whitney Sum test showed that slightly greater tumor size (P=0.03), elevated lymphatic (P=0.005) and distant (P<0.001) metastasis rate, higher pathological grade (P<0.001), localized tumor number (P<0.001), and shortened survival months (P<0.001) were observed in the PAP+ group compared with the PAP- group. In the multivariable logistic regression, invasion and metastasis Hazard Ratio (HR) were elevated significantly (P<0.001) in the PAP+ individuals. In the survival analysis, PAP- patients experienced the prolonged median survival. In the postsurgical patients, the survival months were still longer in PAP+ patients compared with the negative ones (P<0.001), though surgery prolonged the survival months of both groups. Survival months stratified by localized, invasion, and metastasis situations were analyzed. In the three stratified subgroups, the survival duration is significantly decreased in the PAP+ individuals in the localized PCa group (P<0.001) and the metastasis group (P=0.013).Conclusions. The findings of this study provide population-based estimates of the PCa progress and prognosis for patients with different PAP results, which may suggest a renewed period for the PAP.

Human semen contains a large number of macromolecules, including proteins/enzymes and carbohydrates, regulating and protecting sperm cells. Proteomic analysis of human seminal fluid led to the discovery of semen amyloids derived from short peptide fragments of the proteins prostatic acid phosphatase (PAP) and semenogelin (SG) which are known to play a crucial role in enhancing HIV infection. However, the relevance of their existence in human semen and role in maintaining sperm behavior remains unclear. Distinct physiological, biochemical, and biophysical attributes might cause these amyloids to influence sperm behavior positively or negatively, affecting fertilization or other reproductive processes. We assessed the direct effect of amyloids derived from a PAP248–286 fragment, on sperm motility and viability, which are crucial parameters for assessment of sperm quality in semen. Co-incubation of human sperm with PAP248–286 amyloids at normal physiological concentrations formed in buffer led to significant reduction in sperm viability, though approximately a 10× higher concentration was needed to show a similar effect with amyloid formed in seminal fluid. Both forms of PAP248–286 amyloid also had a significant impact on sperm motility at physiological levels, in agreement with a previous report. Our study suggests that PAP248–286 amyloids can directly influence sperm motility and viability in a concentration-dependent manner. We hypothesise that the direct toxic effect of PAP248–286 amyloid is normally mitigated by other seminal fluid ingredients, but that in pathological conditions, where PAP248–286 concentrations are elevated and it plays a role in determining sperm health and viability, with relevance for male fertility as well as sterility.

Adoptive cell transfer (ACT) is an emerging immunotherapy technique that restricts tumor growth and invasion in cancer patients. Among the different types of ACT, chimeric antigen receptor (CAR)T‑cell therapy is considered to be the most advanced and a potentially powerful technique for the treatment of cancer in clinical trials. The primary aim of CART‑cell therapy is to destroy cancer cells and therefore, it serves an important role in tumor immunotherapy. CART‑cell therapy has been demonstrated to mainly treat blood cancer by targeting cluster of differentiation (CD)‑19, CD20, CD22, CD33 and CD123. However, the use of CART‑cell therapy for treating solid tumors is currently under extensive investigation. With respect to prostate cancer, prostatic acid phosphatase, prostate‑specific antigen, prostate‑specific membrane antigen (PSMA), prostate stem cell antigen, T‑cell receptor γ alternate reading frame protein, transient receptor potential‑p8 and six‑transmembrane epithelial antigen of the prostate 1 are among the identified target antigens for prostate tumors. However, mesothelin, fibroblast activation protein, epidermal growth factor receptor, carcinoembryonic antigen, disialoganglioside‑2 and human epidermal growth factor 2 are among the main targets of CART‑cell therapy in the case of other types of solid tumors. The main challenges in CART‑cell therapy are the selection of the target antigens and the modulation of the ideal tumor microenvironment for T‑cells to fight against the cancer. The present review focuses on the 1st, 2nd, 3rd and 4th generations of anti‑PSMA CARs and their application for combating prostate carcinoma.

Peptide-based cancer vaccines are able to induce strong immune responses, but their clinical results are unsatisfactory. To determine clinically correlated peptides, we analyzed survival data from urological cancer patients treated by personalized peptide vaccination (PPV), in which different multiple peptides were used for individual patients based on human leukocyte antigen (HLA) type and pre-existing immunity. Survival data were obtained from a database of 265 urological cancer patients treated in 5 clinical PPV trials comprising 154 patients with castration-resistant prostate cancer (CRPC) and 111 patients with advanced urothelial cancer (UC). Expression of tumor-associated antigens (TAA) was evaluated in 10 prostate cancer tissues, 4 metastatic lymph nodes from prostate cancer, and 10 UC tissues using immunohistochemical staining. Clinical efficacy of individual peptides for overall survival was evaluated by the Cox proportional hazards regression model. All TAA coding candidate peptides used in PPV treatment were expressed in tumor cells from prostate cancer and UC samples except for p56Lck in both, and prostate-specific antigen (PSA), prostatic acid phosphatase (PAP) and prostate-specific membrane antigen (PSMA) in the UC samples. Patients with the following peptides had a significantly longer survival than patients without the peptides (hazard ratio

Purpose Although localized prostate cancer (PCa) is multifocal, the dominant intraprostatic nodule (DIN) is responsible for disease progression after radiation therapy. PCa expresses antigens that could be recognized by the immune system. We therefore hypothesized that stereotactic dose escalation to the DIN is safe, may increase local control, and may initiate tumor-specific immune responses. Patients and Methods Patients with localized PCa were treated with stereotactic extreme hypofractionated doses of 36.25 Gy in 5 fractions to the whole prostate while simultaneously escalating doses to the magnetic resonance image–visible DIN (45 Gy, 47.5 Gy, and 50 Gy in 5 fractions). The phase 1a part was designed to determine the recommended phase 1b dose in a “3 + 3” cohort-based, dose-escalation design. The primary endpoint was dose-limiting toxicities defined as ≥grade 3 gastrointestinal (GI) or genitourinary (GU) toxicity (or both) by National Cancer Institute Common Terminology Criteria for Adverse Events (version 4) up to 90 days after the first radiation fraction. The secondary endpoints were prostate-specific antigen kinetics, quality of life (QoL), and blood immunologic responses. Results Nine patients were treated in phase 1a. No dose-limiting toxicities were observed at either level, and therefore the maximum tolerated dose was not reached. Further characterization of tolerability, efficacy, and immunologic outcomes was conducted in the subsequent 11 patients irradiated at the highest dose level (50 Gy) in the phase 1b expansion cohort. Toxicity was 45% and 25% for grades 1 and 2 GU, and 20% and 5% for grades 1 and 2 GI, respectively. No grade 3 or worse toxicity was reported. The average (±standard error of the mean) of the QoL assessments at baseline and at 3-month posttreatment were 0.8 (±0.8) and 3.5 (±1.5) for the bowel (mean difference, 2.7; 95% confidence interval, 0.1-5), and 6.4 (±0.8) and 7.27 (±0.9) for the International Prostate Symptom Score (mean difference, 0.87; 95% confidence interval, 0.3-1.9), respectively. A subset of patients developed antigen-specific immune responses against prostate-specific membrane antigen (n = 2), prostatic acid phosphatase (n = 1), prostate stem cell antigen (n = 4), and prostate-specific antigen (n = 2). Conclusions Irradiation of the whole prostate with 36.25 Gy in 5 fractions and dose escalation to 50 Gy to the DIN was tolerable and determined as the recommended phase 1b dose. This treatment has promising antitumor activity, which will be confirmed by the ongoing phase 2 part. Preliminary QoL analysis showed minimal impact in GU, GI, and sexual domains. Stereotactic irradiation induced antigen-specific immune responses in a subset of patients.

Prostate cancer is now the most common cancer diagnosed in men in Australia,1 and Australia has one of the highest incidence rates of prostate cancer in the world, with an estimated age-standardised rate of 119.2 per 100 000 men.2 Before 1960, the primary diagnostic test for prostate cancer was the prostatic acid phosphatase test. This was eventually replaced in the1980s by the prostate-specific antigen (PSA) test. Refereed/Peer-reviewed

Recently, increasing data show that immunotherapy could be a powerful weapon against cancers. Comparing to the traditional surgery, chemotherapy or radiotherapy, immunotherapy more specifically targets cancer cells, giving rise to the opportunities to the patients to have higher response rates and better quality of life and even to cure the disease. Cancer vaccines could be designed to target tumor-associated antigens (TAAs), cancer germline antigens, virus-associated antigens, or tumor-specific antigens (TSAs), which are also called neoantigens. The cancer vaccines could be cell-based (e.g., dendritic cell vaccine provenge (sipuleucel-T) targeting prostatic acid phosphatase for metastatic prostate cancer), peptide/protein-based, or gene- (DNA/RNA) based, with the different kinds of adjuvants. Neoantigens are tumor-specific and could be presented by MHC molecules and recognized by T lymphocytes, serving the ideal immune targets to increase the therapeutic specificity and decrease the risk of nonspecific autoimmunity. By targeting the shared antigens and private epitopes, the cancer vaccine has potential to treat the disease. Accordingly, personalized neoantigen-based immunotherapies are emerging. In this article, we review the literature and evidence of the advantage and application of cancer vaccine. We summarize the recent clinical trials of neoantigen cancer vaccines which were designed according to the patients’ personal mutanome. With the rapid development of personalized immunotherapy, it is believed that tumors could be efficiently controlled and become curable in the new era of precision medicine.

Sipuleucel-T, an autologous cellular immunotherapy manufactured from antigen-presenting cells primed to recognize prostatic acid phosphatase, was the first immunotherapy product approved by the US FDA. It was approved for men with asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer after it was shown to provide a survival advantage. Additional studies have examined its use in other clinical settings and in combination with other approved and investigational immunotherapy agents. This review will discuss the pivotal trials leading to approval, will outline some of the biomarkers associated with its efficacy and will review some of the ongoing combination strategies. Maximizing the efficacy of sipuleucel-T through better patient selection or through combination approaches remains the challenge of the future.

Photobiomodulation (PBM) is a simple, efficient and cost-effective treatment for both acute and chronic pain. We previously showed that PBM applied to the mouse head inhibited nociception in the foot. Nevertheless, the optimum parameters, location for irradiation, duration of the effect, and the mechanisms of action remain unclear. In the present study, the pain threshold in the right hind-paw of mice was studied, after PBM (810 nm CW laser, spot size 1 cm(2) or 6 cm(2), 1.2–36 J/cm(2)) applied to various anatomical locations. The pain threshold, measured with von Frey filaments, was increased more than 3-fold by PBM to the lower back (dorsal root ganglion, DRG), as well as to other neural structures along the pathway such as the head, neck and ipsilateral (right) paw. On the other hand, application of PBM to the contralateral (left) paw, abdomen and tail had no effect. The optimal effect occurred 2–3 hours post-PBM and disappeared by 24 hours. Seven daily irradiations showed no development of tolerance. Type 1 metabotropic glutamate receptors decreased, and prostatic acid phosphatase and tubulin-positive varicosities were increased as shown by immunofluorescence of DRG samples. These findings elucidate the mechanisms of PBM for pain and provide insights for clinical practice.

Made available in DSpace on 2018-11-28T20:01:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) An innovative and sensitive label-free electrochemical biosensor platform for detecting human prostatic acid phosphatase (hPAP) is proposed herein. The methodology uses impedance-derived immittance functions (ImFs) for monitoring the interfacial changes in a hPAP bio-recognition layer constructed using a self-assembled monolayer of PEGlate thiol (low-fouling materials) and 11-ferrocenyl undecanethiol (redox probe confined). We evaluated the response toward the target primarily in phosphatase-buffered saline, at varying concentrations and across a wide range of frequencies. The optimum frequency for each ImF parameter was selected based on its sensitivity and linearity within a target concentration ranging from 20 pM to 5000 pM and a limit of detection (LoD) below the cut-off value for this cancer biomarker (10 pM). The best ImF selected (inverse of imaginary capacitance, 1/C?) was then successfully used to monitor hPAP in human blood serum and showed a linear range from 50 pM to 104 pM, with an LoD of 11.2 +/- 2.6 pM. Additionally, both the assay and analysis of the results can be performed in a few minutes without the need to add an interfering redox probe to the biological samples, thus providing a rapid, sensitive, and label-free test for prostate cancer. (C) 2017 Elsevier B.V. All rights reserved. Sao Paulo State Univ, Nanob Grp, Inst Chem, BR-14800900 Sao Paulo, Brazil Sao Paulo State Univ, Nanob Grp, Inst Chem, BR-14800900 Sao Paulo, Brazil

Neuroendocrine-differentiated prostate cancer cells may contribute to androgen-independent proliferation of surrounding cells through Ca(2+)-dependent secretion of mitogenic factors. Human prostate cancer LNCaP cells, when neuroendocrine-differentiated, overexpress Cav3.2 T-type Ca(2+) channels that contribute to Ca(2+)-dependent secretion. Given evidence for the acceleration of Cav3.2 activity by hydrogen sulfide (H2S), we examined the roles of the H2S/Cav3.2 pathway and then analyzed the molecular mechanisms of the Cav3.2 overexpression in neuroendocrine-differentiated LNCaP cells. LNCaP cells were differentiated by dibutyryl cyclic AMP. Protein levels and T-type Ca(2+) channel-dependent currents (T-currents) were measured by immunoblotting and whole-cell pacth-clamp technique, respectively. Spontaneous release of prostatic acid phosphatase (PAP) was monitored to evaluate secretory function. The differentiated LNCaP cells exhibited neurite outgrowth, androgen-independent proliferation and upregulation of mitogenic factors, and also showed elevation of Cav3.2 expression or T-currents. Expression of cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS), H2S-forming enzymes, and spontaneous secretion of PAP increased following the differentiation. The augmented T-currents were enhanced by H2S donors and suppressed by inhibitors of CSE, but not CBS. The PAP secretion was reduced by inhibition of CSE or T-type Ca(2+) channels. During differentiation, Egr-1 and REST, positive and negative transcriptional regulators for Cav3.2, were upregulated and downregulated, respectively, and Egr-1 knockdown prevented the Cav3.2 overexpression. Our data suggest that, in neuroendocrine-differentiated LNCaP cells, H2S formed by the upregulated CSE promotes the activity of the upregulated Cav3.2, leading to the elevated secretory functions. The overexpression of Cav3.2 appears to involve upregulation of Egr-1 and downregulation of REST.

BACKGROUND Prostate adenocarcinoma is the most common form of prostate cancer. We have previously shown in a murine model that prostatic acid phosphatase (PAP) deficiency leads to increased cell proliferation and development of prostate adenocarcinoma. The association between PAP and prostate cancer has been reported. Indeed, high PAP enzymatic activity is detected in the serum of patients with metastatic disease while its expression is reduced in prostate cancer tissue. However, the molecular mechanisms behind the onset of the disease remains poorly understood. We previously identified a novel transmembrane prostatic acid phosphatase (TMPAP) isoform, which interacts with snapin. TMPAP is expressed on the plasma membrane, as well as endosomal/lysosomal and exosomal membrane vesicles by means of a tyrosine-based lysosomal targeting motif (Yxxϕ). METHODS We used stable overexpression of the secreted isoform (SPAP) and TMPAP in LNCaP cells, live cell imaging, microarray and qRT-PCR analyses, and fluid phase uptake of HRP and transferrin. RESULTS Our results indicate that the stable overexpression of TMPAP, but not SPAP in LNCaP cells reduces cell growth while increasing endo/exocytosis and cell size. Specifically, cells overexpressing TMPAP accumulate in the G1 phase of the cell cycle, and show altered gene expression profile. CONCLUSIONS Our data suggests that TMPAP may function as a non-canonical tumor suppressor by delaying cell growth in G1 phase of the cell cycle. Prostate 76:151–162, 2016. © 2015 Wiley Periodicals, Inc.

Semen harbors amyloid fibrils formed by proteolytic fragments of prostatic acid phosphatase (PAP248-286 and PAP85-120) and semenogelins (SEM1 and SEM2) that potently enhance HIV infectivity. Amyloid but not soluble forms of these peptides enhance HIV infection. Thus, agents that remodel these amyloid fibrils could prevent HIV transmission. Here, we confirm that the green tea polyphenol, epigallocatechin-3-gallate (EGCG), slowly remodels fibrils formed by PAP248-286 termed SEVI (semen derived enhancer of viral infection) and also exerts a direct anti-viral effect. We elucidate for the first time that EGCG remodels PAP85-120, SEM1(45-107), and SEM2(49-107) fibrils more rapidly than SEVI fibrils. We establish EGCG as the first small molecule that can remodel all four classes of seminal amyloid. The combined anti-amyloid and anti-viral properties of EGCG could have utility in preventing HIV transmission.

Smoking, passive smoking, and nonsmoking are conditions that give different degrees of stress to the body. In this study, a proteomic technique was used to analyze differentially urinary protein expression between these three groups of subjects. Urinary proteins were precipitated using ammonium sulfate followed by separation according to molecular weights using SDS-PAGE. The gel was stained by Coommassie blue, and the image of the gel was captured for the comparison study. The protein bands that were consistently detected but expressed at different intensity between the smokers and nonsmokers were targeted for further analysis. Three targeted protein bands were excised from the gel, consisting of a unique protein band of smokers and a pair of differentially expressed protein bands from smokers and nonsmokers. The proteins were digested in gel by trypsin. The tryptic peptides were analyzed with ultra performance liquid chromatography-tandem mass spectrometry. Protein identity was determined by the product ion spectrum in the MS/MS scan. Four unique proteins from the smokers, namely, pancreatic alpha amylase, proepidermal growth factor, protein 4.1, and prostatic acid phosphatase, were found to be potential urinary biomarkers to indicate smoking status of a person.

Prostate-specific antigen (PSA) is a glycoprotein produced by prostatic duct and acinar epithelial cells and the most commonly used marker for diagnosing prostate cancer, and for monitoring its progression and recurrence. Here, we describe a 76-year-old patient with recurrent prostate cancer who developed isolated hematogenous pulmonary metastases with a normal serum PSA level 5 years after radical prostatectomy. Immunohistochemical (IHC) analysis of a transbronchial lung biopsy specimen revealed tumor cells positive for PSA and prostatic acid phosphatase. After 2 months of maximal androgen blockade, the metastatic pulmonary nodules showed near-complete regression. In conclusion, metastases of prostate adenocarcinoma may occur despite low serum PSA levels, and, if warranted clinically, IHC staining or other serological markers for prostate adenocarcinoma should be considered when evaluating metastatic carcinoma from an unknown primary lesion in males with low serum PSA levels. (Korean J Med 2015;89:238-242)

Prostatic acid phosphatase (PAP) assembles into amyloid fibrils that facilitate infection by HIV. Its peptide fragments PAP(248–286) and PAP(85–120) also enhance attachment of the virus by viral adhesion to the host cell prior to receptor-specific binding via reducing the electrostatic repulsion between the membranes of the virus and the target cell. The secondary structure of monomeric PAP(248–286) in a biomembrane-mimicking environment can be separated into an N-terminal unordered region, an α-helical central domain, and an α/310-helical C-terminal section (Nanga et al., J. Am. Chem. Soc., 131:17972–17979, 2009). In this work, we used two-dimensional nuclear magnetic resonance (2D NMR) spectroscopy techniques to study spatial structures of isolated central [PAP(262–270)] and C-terminal [PAP(274–284)] fragments of PAP(248–286) in SDS micelle solutions. NMR studies revealed the formation of complexes of both peptides with SDS micelles, with attraction to the micelle membranes occurring mainly through nonpolar and uncharged residues of the peptides. We demonstrate that, when interacting with SDS micelles, PAP(262–270) and PAP(274–284) form α-helical and 310-helical secondary structures, respectively, similar to that found previously for the 39-residue PAP(248–286).

The high relapse rate of prostate cancer following radical prostatectomy is clinically problematic, and various neoadjuvant therapies aimed at reducing the rate have been examined. A previous study has shown that immune responses are increased in patients treated by adenoviral vector-mediated herpes simplex virus-thymidine kinase (HSV-tk) gene delivery followed by ganciclovir (GCV) injection. However, details of the immune responses following this form of gene therapy remain unclear. Five patients who agreed to participate in the present phase I/II trial were repeatedly administered GCV intravenously for 2 weeks following intraprostatic injection of HSV-tk. Peripheral blood samples were periodically collected following the treatments, and lymphocyte subsets were analyzed by flow-cytometry. Intracellular interferon (IFN)-γ produced by T cells was further measured in response to prostatic acid phosphatase and NY-ESO-1 overlapping peptides. Central memory (CM) cluster of differentiation 8+ (CD8+) T cells were found to increase markedly during the second round of treatment. In three patients, tumor antigen-specific T cells were clearly increased following HSV-tk + GCV treatment. An increase in prostate cancer antigen-specific T cells and CM CD8+ T cells may contribute to a reduction of relapse rates in prostate cancer patients receiving this form of gene therapy, which shows promise in a neoadjuvant setting.

Background Understanding the progression of prostate cancer to androgen-independence/castrate resistance and development of preclinical testing models are important for developing new prostate cancer therapies. This report describes studies performed 30 years ago, which demonstrate utility and shortfalls of xenografting to preclinical modeling. Methods We subcutaneously implanted male nude mice with small prostate cancer fragments from transurethral resection of the prostate (TURP) from 29 patients. Successful xenografts were passaged into new host mice. They were characterized using histology, immunohistochemistry for marker expression, flow cytometry for ploidy status, and in some cases by electron microscopy and response to testosterone. Two xenografts were karyotyped by G-banding. Results Tissues from 3/29 donors (10%) gave rise to xenografts that were successfully serially passaged in vivo. Two, (UCRU-PR-1, which subsequently was replaced by a mouse fibrosarcoma, and UCRU-PR-2, which combined epithelial and neuroendocrine features) have been described. UCRU-PR-4 line was a poorly differentiated prostatic adenocarcinoma derived from a patient who had undergone estrogen therapy and bilateral castration after his cancer relapsed. Histologically, this comprised diffusely infiltrating small acinar cell carcinoma with more solid aggregates of poorly differentiated adenocarcinoma. The xenografted line showed histology consistent with a poorly differentiated adenocarcinoma and stained positively for prostatic acid phosphatase (PAcP), epithelial membrane antigen (EMA) and the cytokeratin cocktail, CAM5.2, with weak staining for prostate specific antigen (PSA). The line failed to grow in female nude mice. Castration of three male nude mice after xenograft establishment resulted in cessation of growth in one, growth regression in another and transient growth in another, suggesting that some cells had retained androgen sensitivity. The karyotype (from passage 1) was 43–46, XY, dic(1;12)(p11;p11), der(3)t(3:?5)(q13;q13), -5, inv(7)(p15q35) x2, +add(7)(p13), add(8)(p22), add(11)(p14), add(13)(p11), add(20)(p12), -22, +r4[cp8]. Conclusions Xenografts provide a clinically relevant model of prostate cancer, although establishing serially transplantable prostate cancer patient derived xenografts is challenging and requires rigorous characterization and high quality starting material. Xenografting from advanced prostate cancer is more likely to succeed, as xenografting from well differentiated, localized disease has not been achieved in our experience. Strong translational correlations can be demonstrated between the clinical disease state and the xenograft model. Prostate 75: 628–636, 2015. © The Authors. The Prostate published by Wiley Periodicals, Inc.

Background Immunotherapies have demonstrated clinical benefit for many types of cancers, however many patients do not respond, and treatment-related adverse effects can be severe. Hence many efforts are underway to identify treatment predictive biomarkers. We have reported the results of two phase I trials using a DNA vaccine encoding prostatic acid phosphatase (PAP) in patients with biochemically recurrent prostate cancer. In both trials, persistent PAP-specific Th1 immunity developed in some patients, and this was associated with favorable changes in serum PSA kinetics. In the current study, we sought to determine if measures of antigen-specific or antigen non-specific immunity were present prior to treatment, and associated with subsequent immune response, to identify possible predictive immune biomarkers. Methods Patients who developed persistent PAP-specific, IFNγ-secreting immune responses were defined as immune “responders.” The frequency of peripheral T cell and B cell lymphocytes, natural killer cells, monocytes, dendritic cells, myeloid derived suppressor cells, and regulatory T cells were assessed by flow cytometry and clinical laboratory values. PAP-specific immune responses were evaluated by cytokine secretion in vitro, and by antigen-specific suppression of delayed-type hypersensitivity to a recall antigen in an in vivo SCID mouse model. Results The frequency of peripheral blood cell types did not differ between the immune responder and non-responder groups. Non-responder patients tended to have higher PAP-specific IL-10 production pre-vaccination (p = 0.09). Responder patients had greater preexisting PAP-specific bystander regulatory responses that suppressed DTH to a recall antigen (p = 0.016). Conclusions While our study population was small (n = 38), these results suggest that different measures of antigen-specific tolerance or regulation might help predict immunological outcome from DNA vaccination. These will be prospectively evaluated in an ongoing randomized, phase II trial. Electronic supplementary material The online version of this article (doi:10.1186/s40425-017-0260-3) contains supplementary material, which is available to authorized users.

Aims: Determining the origin of metastases is an important task of pathologists to allow for the initiation of a tumor-specific therapy. Recently, homeobox protein Hox-B13 (HOXB13) has been suggested as a new marker for the detection of prostatic origin. The aim of this study was to evaluate the diagnostic sensitivity of HOXB13 in comparison to commonly used immunohistochemical markers for prostate cancer. Materials and methods: Histologically confirmed prostate cancer lymph node metastases from 64 cases were used to test the diagnostic value of immunohistochemical markers: prostate specific antigen (PSA), Prostatic acid phosphatase (PSAP), prostate specific membrane antigen (PSMA), homeobox gene NKX3.1, prostein, androgen receptor (AR), HOXB13, and ETS-related gene (ERG). All markers were evaluated semi-quantitatively using Remmele's immune reactive score. Results: The detection rate of prostate origin of metastasis for single markers was 100% for NKX3.1, 98.1% for AR, 84.3% for PSMA, 80.8% for PSA, 66% for PSAP, 60.4% for HOXB13, 59.6% for prostein, and 50.0% for ERG. Conclusions: Our data suggest that HOXB13 on its own lacks sensitivity for the detection of prostatic origin. Therefore, this marker should be only used in conjunction with other markers, preferably the highly specific PSA. The combination of PSA with NKX3.1 shows a higher sensitivity and thus appears preferable in this setting. View Full-Text

This study investigated the effect of short-term oral exposure to nano-sized titanium dioxide (nTiO2) on Wistar rat prostate and testis, and the associating reproductive-related alterations. The study also evaluated the potential ameliorative effect of the natural flavonoid, morin, on nTiO2-induced aberrations. Intragastric administration of nTiO2 (50mg/kg/day for 1, 2 and 3weeks) increased testicular gamma-glutamyltransferase (γ-GT) activity and decreased testicular steroidogenic acute regulatory protein (StAR) and c-kit gene expression, serum testosterone level and sperm count. nTiO2-treated rats also exhibited prostatic and testicular altered glutathione levels, elevated TNF-α levels, up-regulated Fas, Bax and caspase-3 gene expression, down-regulated Bcl-2 gene expression and enhanced prostatic lipid peroxidation. Sperm malformation and elevated testicular acid phosphatase (ACP) activity and malondialdehyde level, serum prostatic acid phosphatase activity, prostate specific antigen (PSA), gonadotrophin and estradiol levels occurred after the 2 and 3week regimens. Morin (30mg/kg/day administered intragastrically for 5weeks) mitigated nTiO2-induced prostatic and testicular injury as evidenced by lowering serum PSA level, testicular γ-GT and ACP activities and TNF-α level, along with hampering both intrinsic and extrinsic apoptotic pathways. Moreover, morin alleviated prostatic lipid peroxidation, raised prostatic glutathione level, and relieved testicular reductive stress. Additionally, morin increased testicular StAR and c-kit mRNA expression, raised the sperm count, reduced sperm deformities and modified the altered hormone profile. Histopathological evaluation supported the biochemical findings. In conclusion, morin could ameliorate nTiO2-induced prostatic and testicular injury and the corresponding reproductive-related aberrations via redox regulatory, anti-inflammatory and anti-apoptotic mechanisms, promoting steroidogenesis and spermatogenesis, and improving sperm count and morphology.

In this study, prostatic acid phosphatase (PAP), which is overexpressed in human prostate cancer cells, was cloned to be fused to the IgM constant fragment (Fc) for enhancing immunogenicity and expressed in transgenic tobacco plants. Then, the transgenic plants were propagated by in vitro tissue subculture. Gene insertion and expression of the recombinant PAP-IgM Fc fusion protein were confirmed in each tested the first, second, and third subculture generations (SG1, SG2, and SG3, respectively). Transcription levels were constantly maintained in the SG1, SG2 and SG3 leaf section [top (T), middle (M), and base (BA)]. The presence of the PAP-IgM Fc gene was also confirmed in each leaf section in all tested subculture generations. RNA expression was confirmed in all subculture generations using real-time PCR and quantitative real-time PCR. PAP-IgM Fc protein expression was confirmed in all leaves of the SG1, SG2, and SG3 recombinant transgenic plants by using quantitative western blotting and chemiluminescence immunoassays. These results demonstrate that the recombinant protein was stably expressed for several generations of in vitro subculture. Therefore, transgenic plants can be propagated using in vitro tissue subculture for the production of recombinant proteins.

Rabbit antiserum raised against the crude extract of normal human prostatic tissue contained antibodies to a prostatic tissue-specific antigen as shown by immunoprecipitation techniques. Using this antiserum a prostate antigen was detected in normal, benign hypertrophic, and malignant prostatic tissues, but not in other human tissues. The prostate antigen was purified to homogeneity from prostatic tissues and showed a single protein band on analytical polyacrylamide gel electrophoresis and isoelectric focusing. This report thus presents the first demonstration of the purification of a prostate-specific antigen that does not represent prostatic acid phosphatase.

Development and gross anatomical features Lobes and zones Microstructure and functional regulation Components of prostatic fluid Disorders of prostate gland

Prostatitis, BPH, and P.Ca are the most frequent pathologies of the prostate gland that are responsible for morbidity in men. Raised levels of PSA are seen in different pathological conditions involving the prostate. PAP levels are altered in inflammatory or infectious or abnormal growth of the prostate tissue. Serum calcium and phosphorus levels were also found to be altered in prostate cancer and BPH. The present study was carried out to study the levels of PSA, PAP, calcium, and phosphorus in serum of patients with Prostatitis, BPH, or P.Ca and also to evaluate the relationship between them. Males in the age group of 50–85 years with LUTS disease symptoms and with PSA levels more than 4 ng/mL were included. A total of 114 patients were analyzed including 30 controls. Prostatitis in 35.7% of cases, BPH in 35.7% of the cases, and P.Ca in 28.57% of the cases were observed. Thus, the nonmalignant cases constitute a majority. PSA, a marker specific for prostatic conditions, was significantly high in all the diseases compared to controls. A rise in serum PSA and PAP indicates prostatitis or, in combination with these two tests, decreased serum calcium shows advanced disease.

Objective: To evaluate the in vivo anti-androgenic, antioxidant activity and anti-estrogenic activities of Eremomastax speciosa (E. speciosa) in order to find new method for fighting against chronic diseases such as cancer. Methods: Evaluations of antiandrogenic and antioxidant activities were carried out on male rate receiving simultaneous daily administration of testosterone and different doses of aqueous extract of E. speciosa, during a period of 10 d. The evaluation of antiestrogenic activity was carried out on mature ovariectomized female rats receiving simultaneous daily administration of estradiol and different doses of extract, for a week. Then reproductive organs were weighted, levels of prostatic acid phosphatase, superoxide dismutase and catalase as well as some hematologic parameters were measured. Results: The treatment significantly reduced (P

Antisense oligonucleotides (oligos) have been administered against prostatic LNCaP cells in both in vivo and in vitro models. While most oligos consist of a single mRNA binding site targeting a single gene product, or others having sequence homology, we evaluate bispecifics directed towards two unrelated proteins. In LNCaP cells we identified bispecifics which increase the expression of prostate specific membrane antigen (PSMA) while not affecting secreted prostate specific antigen (PSA) or prostatic acid phosphatase (PAP). We then postulated that surface antigen expression is increased by bispecifics able to induce interferon (IFN-γ) through complementary intrastrand regions. To further test this hypothesis we measured the effect of oligo treatment on another secreted product, prostatic cancer antigen-3 (PCA-3). We initially evaluated the inhibition of in vitro propagating LNCaP cells employing mono- and bispecific oligos directed against bcl-2 (the second bispecific binding site was against the epidermal growth factor receptor (EGFR)). These oligos were administered with lipofectin in a nanoparticle delivery system. Employing RT-PCR, the expression of non-targeted genes products encoding PSMA, PSA, PAP, PCA-3 and IFN-γ have now been evaluated. When LNCaP prostate tumor cells were incubated with oligos and compared to lipofectin containing controls significant growth inhibition resulted. Employing RT-PCR, the levels of mRNA encoding PSMA were unexpectedly found to be elevated following treatment with the bispecific oligos but not with a monospecific directed solely against bcl-2. No increased expression in PSA, PAP or PCA-3 following treatment with either oligo type were detected. Like PSMA, IFN-γ was significantly induced only by bispecific oligos. These data support the hypothesis that double strand forming bispecific oligos induce IFN-γ, enhancing cell surface antigen expression (PSMA) but not secretory products. Expression of tumor associated surface antigens could increase their recognition and targeting by immunologic defense mechanisms and increase the effectiveness of tumor vaccines.

We have previously shown that in addition to the well-known secreted isoform of prostatic acid phosphatase (sPAP), a transmembrane isoform exists (TMPAP) that interacts with snapin (a SNARE-associated protein) and regulates the endo-/exocytic pathways. We have also shown that PAP has 5′-ectonucleotidase and thiamine monophosphatase activity and elicits antinociceptive effects in mouse models of chronic inflammatory and neuropathic pain. Therefore, to determine the physiological role of PAP in a typical exocrine organ, we studied the submandibular salivary gland (SMG) of PAP−/− and wild-type C57BL/6J mice by microarray analyses, microRNA sequencing, activity tests, immunohistochemistry, and biochemical and physiological analyses of saliva. We show that PAP is the main acid phosphatase in the wild-type male mouse saliva, accounting for 50% of the total acid phosphatase activity, and that it is expressed only in the granular convoluted tubules of the SMGs, where it is the only 5′-ectonucleotidase. The lack of PAP in male PAP−/− mice was associated with a significant increase in the salivation volume under secretagogue stimulation, overexpression of genes related to cell proliferation ( Mki67, Aurkb, Birc5) and immune response ( Irf7, Cxcl9, Ccl3, Fpr2), and upregulation of miR-146a in SMGs. An increased and sustained acinar cell proliferation was detected without signs of glandular hyperplasia. Our results indicate that in PAP−/− mice, SMG homeostasis is maintained by an innate immune response. Additionally, we suggest that in male mice, PAP via its 5′-ectonucleotidase activity and production of adenosine can elicit analgesic effects when animals lick their wounds.

Immunotherapy has been investigated in both preclinical studies and clinical trials as a new therapy for prostate cancer. Vaccines, including those that utilize dendritic cells, viruses, or DNA, immunize against prostate-specific antigen and prostatic acid phosphatase. The vaccines have long been studied as monotherapy for the cancer, but increasingly more trials have been initiated in combination with other modalities. These include radiation, chemotherapy, and androgen deprivation therapy. This review describes and discusses the various combinations of vaccine immunotherapies.

Treatment options for patients with advanced prostate cancer remain limited and rarely curative. Prostatic acid phosphatase (PAP) is a prostate-specific protein overexpressed in 95% of prostate tumours. An FDA-approved vaccine for the treatment of advanced prostate disease, PROVENGE® (sipuleucel-T), has been shown to prolong survival, however the precise sequence of the PAP protein responsible for the outcome is unknown. As the PAP antigen is one of the very few prostate-specific antigens for which there is a rodent equivalent with high homology, preclinical studies using PAP have the potential to be directly relevant to clinical setting. Here, we show three PAP epitopes naturally processed and presented in the context of HHDII/DR1 (114–128, 299–313, and 230–244). The PAP-114-128 epitope elicits CD4+ and CD8+ T-cell-specific responses in C57BL/6 mice. Furthermore, when immunised in a DNA vector format (ImmunoBody®), PAP-114-128 prevents and reduces the growth of transgenic adenocarcinoma of mouse prostate-C1 prostate cancer cell-derived tumours in both prophylactic and therapeutic settings. This anti-tumour effect is associated with infiltration of CD8+ tumour-infiltrating lymphocytes and the generation of high avidity T cells secreting elevated levels of IFN-γ. PAP-114-128 therefore appears to be a highly relevant peptide on which to base vaccines for the treatment of prostate cancer.

BACKGROUND Prostate cancer cell lines have been used in the search for biomarkers that are suitable for prostate cancer diagnosis. Unfortunately, many cell line studies have only involved single cell lines, partially characterized cell lines or were performed without controls, and this may have been detrimental to effective biomarker discovery. We have analyzed a panel of prostate cancer and nonmalignant control cell lines using current biomarkers and then investigated a set of prospective endosomal and lysosomal proteins to search for new biomarkers. METHODS Western blotting was used to define the amount of protein and specific molecular forms in cell extracts and culture media from a panel of nonmalignant (RWPE-1, PNT1a, PNT2) and prostate cancer (22RV1, CaHPV10, DU-145, LNCaP) cell lines. Gene expression was determined by qRT-PCR. RESULTS HPV-18 transfected cell lines displayed a different pattern of protein and gene expression when compared to the other cell lines examined, suggesting that these cell lines may not be the most optimal for prostate cancer biomarker discovery. There was an increased amount of prostatic acid phosphatase and kallikrein proteins in LNCaP cell extracts and culture media, but variable amounts of these proteins in other prostate cancer cell lines. There were minimal differences in the amounts of lysosomal proteins detected in prostate cancer cells and culture media, but two endosomal proteins, cathepsin B and acid ceramidase, had increased gene and protein expression, and certain molecular forms showed increased secretion from prostate cancer cells (P ≤ 0.05). LIMP-2 gene and protein expression was significantly increased in prostate cancer compared to nonmalignant cell lines (P ≤ 0.05). CONCLUSIONS While the existing prostate cancer biomarkers and lysosomal proteins investigated here were not able to specifically differentiate between a panel of nonmalignant and prostate cancer cell lines, endosomal proteins showed some discriminatory capacity. LIMP-2 is a critical regulator of endosome biogenesis and the increased expression observed in prostate cancer cells indicated that other endosome related proteins may also be upregulated and could be investigated as novel biomarkers. Prostate 74:547–560, 2014. © 2014 Wiley Periodicals, Inc.

CD73, ecto-5′-nucleotidase, is the key enzyme catalyzing the conversion of extracellular AMP to adenosine that controls vascular permeability and immunosuppression. Also prostatic acid phosphatase (PAP) possesses ecto-5′-nucleotidase/AMPase activity and is present in leukocytes. However, its role related to immune system is unknown. Therefore, we analyzed enzymatic activities and leukocyte subtypes of CD73 and PAP knockouts and generated CD73/PAP double knockout mice to elucidate the contribution of CD73 and PAP to immunological parameters. Enzymatic assays confirmed the ability of recombinant human PAP to hydrolyze [3H]AMP, although at much lower rate than human CD73. Nevertheless, 5′-nucleotidase/AMPase activity in splenocytes and lymphocytes from PAP−/−mice tended to be lower than in wild-type controls, suggesting potential contribution of PAP, along with CD73, into lymphoid AMP metabolism ex vivo. Single knockouts had decreased number ofCD4+/CD25+/FoxP3+regulatory T cells in thymus and CD73/PAP double knockouts exhibited reduced percentages of CD4+cells in spleen, regulatory T cells in lymph nodes and thymus, and CD4+and CD8+cells in blood. These findings suggest that PAP has a synergistic role together with CD73 in the immune system by contributing to the balance of leukocyte subpopulations and especially to the number of regulatory T cells in lymph nodes and thymus.

Background: ADXS-PSA, an attenuated Listeria monocytogenes-based immunotherapy targeting prostate-specific antigen (PSA), is currently being evaluated as a treatment for progressive metastatic castration-resistant prostate cancer (mCRPC) in the Phase I/II KEYNOTE-046 trial as a monotherapy (Part A; PA) and in combination with pembrolizumab (Part B; PB). Methods: This Phase I/II trial evaluated pts with mCRPC, ≥18 yrs who received ≤2 prior chemo-/targeted-/immunotherapies or ≤1 prior chemotherapy in a metastatic setting. Part A (PA; n = 13) pts received ADXS-PSA doses 1x109; 5 x109 or 1x1010 CFU IV every 3 wks and Part B (PB; n = 37) pts received 1x109 CFU + 200 mg pembro IV every 3 wks with a 4thpembro dose 3 wks later (in 12 wks cycles), for up to 2 yrs or until progression/toxicity. Safety/tolerability, antitumor activity and effect on PSA levels have been reported for both groups (Stein M et al., Keynote-046, ASCO 2018). Updates on OS and T cell reactivity to PSA and to other prostate cancer antigens (i.e., prostatic acid phosphatase (PAP), prostate-specific membrane antigen (PSMA), prostate stem cell antigen (PSCA), and prostein) are herein presented for PA and PB pts. Results: At entry, PA and PB pts were ~70 yrs with a Gleason score >8 and the majority had received prior abiraterone and/or enzalutamide. PB pts had higher median baseline (BL) PSA (40.6 vs. 20.8 ng/mL), and more prior enzalutamide (53 vs. 26%) and chemotherapy (49 vs. 36%) use vs PA pts. Overall, 2 PA (14%) v 16 PB pts (43%) had a decreased PSA post-BL. Of these, 7 PB (19%) vs. 0 PA pts achieved a confirmed PSA reduction ≥50% from BL. The median OS (months) in PB pts was 23 (17.4 -NR) vs. 8.5 (3.8-20.10) in PA pts. Median OS in PB pts with PSA reduction ≥50% from BL has not been reached as 100% (6/6) of pts are still alive. T cell reactivity, as measured by ELISpot assays, showed that 100% of PA (9/9) pts and 100% of PB (16/16) pts exhibited increases in the frequencies of T cells reactive to at least one prostate cancer antigen other than PSA, which is indicative of antigen spreading. Conclusions: ADXS-PSA ± pembro elicited a broad antitumor T cell response in all mCRPC pts tested but only ADXS-PSA + pembro reduced PSA ≥50% from BL and prolonged OS in these select pts. Clinical trial information: NCT02325557. Citation Format: Mark Stein, Lawrence Fong, Ronald Tutrone, Anthony Mega, Elaine T. Lam, Surya Vangala, Justin Dennie, Robert Petit, Andres Gutierrez, Sandy Hayes, Naomi Haas. KEYNOTE-046: Effects of ADXS-PSA with or without pembrolizumab on survival and antigen spreading in metastatic, castration-resistant prostate cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT098.

5037 Background: Phase I/II studies of pTVG-HP showed safety and increases in prostatic acid phosphatase (PAP)-specific T cells. Based on these, we conducted a multi-center, randomized phase II trial using pTVG-HP with GM-CSF adjuvant vs GM-CSF alone in patients with PSA-recurrent, non-metastatic, non-castrate, prostate cancer (stage M0). Methods: 99 patients with M0 prostate cancer (negative CT and bone scan) with PSA doubling time (DT) of < 12m were randomly assigned to pTVG-HP + GM-CSF vs GM-CSF. Treatments were every 2 wk x 6, and then quarterly for up to 24m. Primary endpoint was 2-year MFS. Secondary endpoints included median MFS, changes in PSA DT, and immune response to PAP antigen. Additional analysis included quantitative changes in bone lesion activity by NaF PET/CT. Results: Few grade 3/4 events were observed and were not statistically different between arms. 2-year MFS between control and pTVG-HP was 42.3% and 41.8% (p = 0.97). Median MFS was not different (18.3m control versus 18.9m pTVG-HP, HR = 1.6, p = 0.13). Changes in PSA DT, and immunity to the PAP target, were not different between study arms. A pre-planned subset analysis showed median MFS was significantly longer in patients with rapid PSA DT ( < 3m) treated with pTVG-HP (6.1m versus 12.0m, n = 21, HR = 4.4, p = 0.03). In patients with baseline metastases detected on NaF PET/CT, total activity (SUVtotal) increased 17% with GM-CSF alone, but decreased 29% with pTVG-HP from baseline to month 6 (n = 27, p = 0.07). Conclusions: This trial did not demonstrate an overall increase in 2-year MFS following treatment with pTVG-HP, but suggested a modest effect in patients with rapidly progressive disease. NaF PET/CT imaging suggests that pTVG-HP has a detectable effect on decreasing metastatic activity in bone. A separate trial suggests that pTVG-HP is an immune activating agent that improves activity of PD-1 blockade. A trial using pTVG-HP in combination with nivolumab in patients with M0 prostate cancer is currently underway. Clinical trial information: NCT01341652.

Our aim is to develop a new and more effective prostatic acid phosphatase (PAP) peptide-based vaccine for the treatment of advanced prostate cancer (PCa). We have previously shown that a 15mer PAP peptide-derived vaccine, when administered as a DNA vaccine, could induce PAP-specific T-cell responses and reduce the growth of implanted murine TRAMP C1-derived tumors in a syngeneic heterotopic murine model. We have subsequently developed an elongated (42mer) PAP-derived peptide in which Alanine at position 115 was replaced by Leucine.Herein, the capacity of the wild-type and mutated PAP-42mer vaccines to induce PAP-specific immune responses were compared in two pre-clinical murine models. The murine PAP-42mer sequence was evaluated in C57Bl/6 mice and the human PAP-42mer sequence in HHDII/DR1 transgenic mice. Following the identification of the most promising PAP-42mer sequence, the capacities of different delivery systems (CpG adjuvant, CAF09 adjuvant and ImmunoBody® DNA vaccine) to generate PAP-specific immunity were compared. For these studies, the responsiveness of splenocytes isolated from immunized mice following in vitro stimulation with MHC class I or class II wild-type vaccine-derived peptides (8/9 or 15 amino-acid long) was assessed using an IFNγ ELISpot assay and by immunophenotyping of splenic T-cells using flow cytometry. The ability of splenocytes to kill relevant targeT-cells after a short in vitro stimulation was assessed using a 51chromium release assay. B16 cells that had been knocked out for beta-2m gene and transfected to express chimeric HLA-A2 (HHDII), HLA-DR1 and human PAP implanted into HHDII/DR1 mice was used as a proof-of-concept model to assess the antitumor efficacy of the hPAP42mer mutated vaccine with CAF09 adjuvant in a prophylactic setting.The mutated murine and human PAP42mer-based vaccines induced a higher number of IFNγ-releasing splenocytes in response to in vitro stimulation with class I or class II vaccine-derived peptides and generated cells having a higher functional avidity. CAF09 and ImmunoBody® were superior to CpG in inducing PAP-specific immune responses, with CAF09 eliciting strong immune responses in both models, and ImmunoBody® eliciting potent immune responses in C57Bl/6 mice. Indeed, a higher proportion of CD8+ T-cells were able to release IFNγ and TNFα, to proliferate (Ki67 expression) and to degranulate (CD107a and Granzyme B expression) after short incubation with MHC class-I peptide. These vaccines strategies were also able to induce a higher proportion of memory CD8+ T-cells and the expression of PD-1 on CD8+ T-cells. Additionally, splenocytes from vaccinated mice were able to kill MHC class I peptide-pulsed targeT-cells (T2 and RMAS cells) and murine PCa cells expressing PAP (TRAMP-C1 cells) in vitro. The vaccine slowed the growth of human-PAP+-B16-derived tumors in HHDII/DR1 model and prolonged the survival (9 days delay for 30% of the mice). Splenic CD8+ T-cells and CD8+ tumor-infiltrating cells from vaccinated mice released IFNγ and TNFα, proliferated and degranulated in response to in vitro stimulation with MHC class I peptide. Finally, multimer-based flow cytometric analysis of peripheral blood mononuclear cells from patients with PCa following in vitro stimulation with PAP-derived peptides demonstrated the presence of PAP42mer-reactive CD8+ T-cells. Ongoing studies are assessing the effect of combining the vaccine with checkpoint inhibition (a PD-1 monoclonal antibody) in a therapeutic setting. In summary, we have developed a vaccine strategy which induces robust anti-PAP immunity and slows the growth of implanted PAP+ cancer cell-derived tumors in vivo. The presence of PAP-specific CD8+ T-cells in the periphery of patients with advanced PCa suggests that these patients will benefit from this new approach, especially when combined with checkpoint inhibition. Citation Format: Pauline Le Vu, Jayakumar Vadakekolathu, Dennis Christensen, Lindy Durrant, Graham Pockley, Stephanie E.B. McArdle. Development of a novel prostatic acid phosphatase-derived vaccine for the treatment of advanced prostate cancer [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr B118.

Three different antihelmintic drugs were used in the present study (ivermectin, levamisole andalbendazole) on Friesian bulls .The animals were divided into four groups (control untreatedgroup, ivermectin, levamisole, and albendazole treated groups, respectively). The drugs used attwo doses with 8 weeks intervals between first and second one at 200μg/kg, 7.5mg/kg and10mg/kg, respectively. Semen samples were collected for 8th weeks after each dose.Biochemical semen characteristics were estimated. The bulls treated with ivermectin showedsignificant increase in semen- ejaculate volume, sperm- cells concentration (x109 / ml), totalsperm output ejaculate (x109 / ml), alkaline phosphatase (ALP) and prostatic acid phosphatase(ACP) activities in seminal plasma, seminal plasma total proteins, globulin, urea and zincconcentration; while significantly decreased seminal plasma alanine-aminotransferase (ALT),aspartate-aminotranferase (AST), and sodium were reported. The bulls treated with levamisoleshowed significant increase in semen-ejaculate volume, total sperm output/ejaculate, ALP andprostatic ACP activities in seminal plasma, seminal plasma total proteins, globulin, urea andzinc concentrations; while significantly decreased seminal plasma ALT, AST, and sodium wererecorded. In contrary, the bulls treated with albendazole were significantly decreased semenejaculatevolume, sperm motility, seminal plasma total proteins, globulin, creatinine andcalcium. Also, it showed significant increase in seminal plasma enzymes activity (ALT, ASTand ALP) and zinc concentrations. It is interest to note that different anthelmintics treatmentused in this study didn’t affect significantly in seminal plasma albumin and total ACP activity.In conclusion: Ivermectin treatment improved semen qualities by increasing seminal volume andconcentration. Anthelmintics treatment with levamisole should be used carefully under controlduring breeding season. Albendazole treatment should be avoided because its harmful effect insemen by decreasing semen-ejaculate volume, sperm motility, seminal plasma total proteins,globulin and increasing seminal plasma aminotransferase enzymes activity.

Summary Galectin-3 is a multifunctional carbohydrate-binding protein that was previously characterized as a proteolytic substrate for prostate-specific antigen (PSA) and was shown to be associated with prostasomes in human semen. Prostasomes are exosome-like vesicles that are secreted by the prostatic epithelium and have multiple proposed functions in normal reproduction and prostate cancer. In the current study, galectin-3 binding ligands in human prostasomes were identified and characterized with the goal to investigate galectin-3 function in prostasomes. Galectin-3 binding proteins were isolated by affinity column chromatography. Candidate ligands identified by MS/MS were PSA, prostatic acid phosphatase (PAP), zinc alpha-2-glycoprotein (ZAG), dipeptidyl peptidase-4 (CD26), aminopeptidase N (CD13), neprilysin, clusterin, antibacterial protein (FALL-39) and alpha-1-acid glycoprotein (ORM1). Biochemical methods were used to characterize the ability of galectin-3 to bind to selected ligands, and galectin-3 cleavage assays were utilized to investigate the protease(s) in prostasomes that cleaves galectin-3. CD26, CD13, PSA, PAP and ZAG immunoreactivity were detected in extracts of purified prostasomes. One-dimensional electroblot analysis of prostasomes demonstrated that CD26, PAP and CD13 immunoreactivity co-migrated with galectin-3-reactive protein bands. PSA and ZAG were found to be associated with the surface of prostasomes. Both intact and cleaved galectin-3 were detected in prostate and prostasome extracts. Cleavage and inhibition assays indicated that PSA in prostasomes proteolytically cleaves galectin-3. The identification of these glycoproteins as galectin-3 ligands lays the groundwork for future studies of galectin-3 and prostasome function in reproduction and prostate cancer.

Prostate cancer (PCa), a highly heterogeneous disease, is the one of the leading cause of morbidity and mortality in the developed countries. Historically used biomarkers such as prostatic acid phosphatase (PAP), serum prostate-specific antigen (PSA), and its precursor have not stood the challenge of sensitivity and specificity. At present, there is need to re-evaluate the approach to diagnose and monitor PCa. To this end, molecular markers that can accurately identify men with PCa at an early stage, and those who would benefit from early therapeutic intervention, are the need of the hour. There has been unprecedented progress in the development of new PCa biomarkers through advancements in proteomics, tissue DNA and protein/RNA microarray, identification of microRNA, isolation of circulating tumor cells, and tumor immunohistochemistry. This review will examine the current status of prostate cancer biomarkers with emphasis on emerging biomarkers by evaluating their diagnostic and prognostic potentials.

The secretory and transmembrane isoforms of Prostatic acid phosphatase (PAP) can dephosphorylate extracellular adenosine 5′-monophosphate (AMP) to adenosine, classifying PAP as an ectonucleotidase. Currently, there are no compounds that inhibit PAP in living cells. To identify small molecule modulators of PAP, we used a 1,536-well based quantitative high-throughput fluorogenic assay to screen the Library of Pharmacologically Active Compounds (LOPAC1280) arrayed as eight-concentration dilution series. This fluorogenic assay used difluoro-4-methylumbelliferyl phosphate (DiFMUP) as substrate and collected data in kinetic mode. Candidate hits were subsequently tested in an orthogonal absorbance-based biochemical assay that used AMP as substrate. From these initial screens, three inhibitors of secretory human (h) and mouse (m)PAP were identified: 8-(4-chlorophenylthio) cAMP (pCPT-cAMP), calmidazolium chloride and nalidixic acid. These compounds did not inhibit recombinant alkaline phosphatase. Of these compounds, only pCPT-cAMP and a related cyclic nucleotide analog [8-(4-chlorophenylthio) cGMP; pCPT-cGMP] inhibited the ectonucleotidase activity of transmembrane PAP in a cell-based assay. These cyclic nucleotides are structurally similar to AMP but cannot be hydrolyzed by PAP. In summary, we identified two cyclic nucleotide analogs that inhibit secretory and transmembrane PAP in vitro and in live cells.

Prostatic acid phosphatase (PAP) is a protein abundantly present in human seminal fluid. PAP plays important role in fertilization. Its 39-amino-acid fragment, PAP(248–286), is effective in enhancing infectivity of HIV virus. In this work, we determined the spatial structure in aqueous solution of a heptapeptide within the PAP fragment, containing amino acid residues 266–272 (Glu-Ile-Leu-Asn-His-Met-Lys). We also report the structure of the complex formed by this heptapeptide with sodium dodecyl sulfate micelles, a model of a biological membrane, as determined by 1H NMR spectroscopy and 2D NMR (TOCSY, HSQC-HECADE, NOESY) spectroscopy. Complex formation was confirmed by chemical shift alterations in the 1H NMR spectra of the heptapeptide, as well as by the signs and values of NOE effects. We also present a comparison of the spatial structure of Glu-Ile-Leu-Asn-His-Met-Lys in water and in complex with sodium dodecyl sulfate.

Prostate cancer is one of the most prevalent non-skin related cancers. It is the second leading cause of cancer deaths among males in most Western countries. If prostate cancer is diagnosed in its early stages, there is a higher probability that it will be completely cured. Prostatic acid phosphatase (PAP) is a non-specific phosphomonoesterase synthesized in prostate epithelial cells and its level proportionally increases with prostate cancer progression. PAP was the biochemical diagnostic mainstay for prostate cancer until the introduction of prostate-specific antigen (PSA) which improved the detection of early-stage prostate cancer and largely displaced PAP. Recently, however, there is a renewed interest in PAP because of its usefulness in prognosticating intermediate to high-risk prostate cancers and its success in the immunotherapy of prostate cancer. Although PAP is believed to be a key regulator of prostate cell growth, its exact role in normal prostate as well as detailed molecular mechanism of PAP regulation is still unclear. Here, many different aspects of PAP in prostate cancer are revisited and its emerging roles in other environment are discussed.

Aims: This study investigated the effect of exposure to arginine (ARG) and glutamate (GLU), or its variant, monosodium glutamate (M SG) on the prostate function and testis histology of rats. Study Design:Exposure to either ARG, GLU, monosodium glutamate (MSG), ARG plus GLU or ARG plus MSG was per oral for 4 consecutive weeks. On the last day of the experiment, rats were food-deprivedfor 15 h before collecting their blood and testis samples.